1. Field of the Invention
This invention relates generally to the fields of biochemistry and medicine, and more specifically to a compounds useful as cancer chemotherapeutic agents.
2. Background Information
Cancer is a leading cause of death in the United States. Despite significant efforts to find new approaches for treating cancer, surgery, chemotherapy and radiation therapy, either alone or in combination, remain the methods of choice. Surgery and radiation therapy, however, generally are useful only for fairly defined cancers and are of limited use for treating patients with disseminated disease.
Chemotherapy is the method of choice for treating patients with metastatic cancer or patients with diffuse cancers such as leukemias. Although chemotherapy can provide a therapeutic benefit in many cancer patients, it often fails to result in cure of the disease due to the patient's cancer cells becoming resistant to the chemotherapeutic agent. Due, in part, to the likelihood of cancer cells becoming resistant to a chemotherapeutic agent, these drugs commonly are used in combination to treat patients.
A continuing effort is being made by individual investigators and by large pharmaceutical companies to identify new, potentially useful chemotherapeutic agents. In some cases, derivatives of known effective drugs are prepared and examined for improved or different, but useful characteristics. In addition, large libraries of randomly synthesized drugs have been prepared and the drugs then examined for potential efficacy as chemotherapeutic agents. Both of these methods have resulted in the identification of useful or potentially useful cancer chemotherapeutic agents.
Efforts also have been made to identify potentially useful drugs that are produced naturally by living organisms. For example, paclitaxel is a chemical that is produced by the yew tree and, when purified, is effective in treating cancers such as ovarian carcinoma. Despite the identification of such new chemotherapeutic agents, additional compounds that can be used to treat diseases such as cancer are needed. The present invention satisfies this need and provides additional advantages.